Colloquium

Junior and senior physics majors attend our biweekly colloquium series,
held on Tuesday afternoons at 4:30 pm in Shanahan B460. The talks are
open to all students and to the public, and are frequently attended by
scientists from the other Claremont Colleges, Cal Poly Pomona, and others. The series
features speakers from a broad range of institutions and fields of physics.

An independent control over electrical and thermal properties is one of the central goals in the search for efficient thermoelectric materials for waste heat energy conversion. A good thermoelectric will have high electrical, but low thermal conductivity. Nature, however, does not seem to favor this dissociation, and the best synthesized thermoelectrics in use today remain at about the same efficiency ...

There appears to be no fundamental reason why macroscopic mechanical objects cannot demonstrate quantum phenomena such as energy quantization, superposition states, and entanglement. In fact, in recent years, researchers have been successful in demonstrating a few of these basic states in the laboratory including the quantum ground state of motion and the exchange of a single quantum with a superconducting ...

Philip Muirhead, Caltech Small Stars with Small Planets and Big Consequences

With the success of NASA’s Kepler Spacecraft, extrasolar planet science has entered a new era. Prior to Kepler’s launch exoplanet science was primarily concerned with gas-giant exoplanets, since gas giants comprised the majority of discoveries, numbering in the hundreds. NASA’s Kepler Mission has since discovered thousands of exoplanets with many of them terrestrial-sized. Of particular interest are terrestrial exoplanets orbiting ...

Maria Spiropulu, Caltech Results from the Highest Energy Proton Collisions at the LHC

The Large Hadron Collider (LHC) is the largest and most complex scientific undertaking ever attempted. Its results will determine the future directions of high-energy physics. The LHC produced 7 TeV proton-proton collisions in 2010 and 2011, and it is expected to produce 14 TeV proton-proton collisions in 2014. Currently it is ramping up for the upcoming run at 8 TeV ...

Graphene, a two-dimensional single atomic layer of carbon, has recently emerged as a promising candidate for electronic materials, as well as a new model system for condensed matter physics. In this talk I will present our work on mechanical, thermal, and electrical properties of suspended graphene devices, such as ripple texturing, negative thermal expansion, spontaneous symmetry breaking and gap formation ...

John M. Martinis, University of California at Santa Barbara Design of a Superconducting Quantum Computer

The computational power of a quantum computer arises from the superposition of quantum states, which gives a net parallel-processing size that exceeds the number of atoms in the universe for even a modest 300-qubit processor. To build such a computer, many groups around the world are exploring whether experimental systems can be controlled sufficiently well and with enough quantum coherence. ...

Two-state quantum systems may be used for encoding information in ways analogous to the bits of a conventional computer. Unlike discrete classical bits, however, quantum bits (qubits) may occupy superposition states in which they are simultaneously both 0 and 1. By manipulating such qubits it is possible to store and process information in new and powerful ways. Computation utilizing these ...

David Hoogerheide, Harvard University Solid State Nanopores as Nanoscale Detectors: Single Molecules, Fast Kinetics, and Ionic Liquids

The advent of nanotechnology has created new possibilities for understanding the world and developing technologies to shape it. Nanoscale devices are useful for studying the behavior of very small numbers of molecules; because of their small size, however, nanodevices are particularly sensitive to fluctuations. One such device is the solid state nanopore, which is a promising platform for next-generation DNA ...

Obtaining information from the environment to guide behavior is one of the most fundamental functions of nervous systems. Since individual cues are rarely 100% reliable, many animals (including humans) combine cues across sensory modalities to improve the quality of their decisions and make their behavior more robust under variable circumstances. In mammals, this "multisensory integration" involves many billions of neurons ...

Photovoltaics are the fastest-growing renewable energy source over the last three years and have the potential to supply a significant fraction of our electricity needs. Conventional silicon cells are made of thick crystals because silicon is a weak absorber in the infrared and much of the visible. Thin solar cells require less energy and material to make and may lead ...

This year’s Nobel prize in physics was given for using Type Ia supernovae as standard candles to discover that dark energy now dominates the dynamics of the universe. Disconcertingly, recent research has uncovered problems with both of the two popular models for Type Ia supernovae. One is in trouble with observational data, and the other with careful theoretical calculations, which ...